Application of Compost to the Soil
Course: Waste in Landscapes and Soils Supervisor: Dr. Matthias Leopold WS 2010/2011
Alessandra Giacometti - matriculation number: 03611250 - firstname.lastname@example.org Olivia Schmid- matriculation number: 03610778 - email@example.com
1. Introduction An ever-increasing world population results in a higher waste production, causing vast environmental impacts. Consequently, the need for recycling has been widely understood and tried to be implemented. Biological waste is one category of waste that steadily increases due to a higher demand for organic food. Besides, thebanning of organic materials from landfills did demand for recycling measures of this sort of waste. Furthermore, the augmentation of agricultural activities and mineral extraction, for example, can severely damage the soil, which requires further sanitation in order to re-establish its natural properties. (Fuchs et al., 2008; Maynard, 2000) In this regard the exaggerated use of chemicalfertilizers is partially responsible for soil degradation, the loss of soil structure, a decline in overall soil quality and a decrease in soil’s nutrient availability (Muldavin, 2000). The production of compost from biological waste and its application to the soil is one option to recycle something that has been previously known as “waste”, thereby closing the loop by returning organic matter andnutrients to the soil. Furthermore, compost helps by mitigating the depletion of organic matter in agricultural land and can reduce the use of chemical fertilizers by increasing the productivity of organic fertilizer, making it more bio-available (Haight, 2000). Hence the use of compost is an alternative for a sustainable and ecologically compatible cultivation which simultaneously protects our limitedresources. However it is decisive for the application of compost to consistently observe the principles of sustainability: composts must produce beneficial and measurable use for plant production and/or soil fertility and at the same time guarantee all interests to protect soils, environment and consumers interests on the medium and long run.
2. Compost 2.1. Definition
Composting is a naturalaerobic decomposition process in which microorganisms transform biological waste into stabilized organic matter. The end-product, the compost, is a homogeneous product, dark and rich in nutrients, and used for soil amendment to improve soil structure, provide nutrients for plants and facilitate the re-vegetation of disturbed and eroded soil. (www.epa.gov; Fuchs et al., 2008; Maynard, 2000)
To initiate composting processes, different requirements need to be fulfilled. Firstly, materials of biological origin (e.g. wood, paper, garden wastes, manure, kitchen trimmings) are needed to create a suitable environment for the microbial activities. The optimal initial matter is a combination of green and moist organic matter with a high N-content (e.g. grass), and brown anddry organic
matter with a high C-content (e.g. leaves), mixed together in the relation 1-2 parts green to 3-4 parts brown. Thereby the more various the material, the less matting and odours, and the smaller the material, the bigger the surface for the microbes and the faster the process. However constraints might occur: especially in biological wastes from households problems with severalorganic pollutants have been noticeable. Packaging material or their additives used for coating or as filler substances may release toxic compounds during biodegradation and severely pollute the compost end-product. (Maynard, 2000)
The process transforming organic matter into compost is based on microbial activities which degrade raw organic materials into a...